The target of rapamycin complex, TORC1, is conserved from yeast to man and has critical roles in sensing and signalling the nutrient and stress status of the cell, thus controlling the balance between cell growth1-5 and cell survival6-11. In budding yeast TORC1 promotes fermentative growth on glucose and down regulates respiration12, 13. TORC1 contains a phosphatidylinositol kinase (PI3-K)-related kinase, either Tor1 or Tor2. The macrolide rapamycin14, in a complex with Fpr1 (Fk506-sensitive Proline Rotamase), binds to Tor1/2 causing cells to enter a state that resembles nutrient limitation15 probably due to a change in the substrate specificity of the Tor kinase16. This new state of the cell is associated with changes in patterns of gene expression, particularly genes required for respiration and stress resistance6,10,17,18. The expression of many TORC1 genes is dependent on the SAGA family of transcriptional co-activator complexes including SAGA (Spt-Ada-Gcn5-Acetyltransferase)19,20, SLIK (SAGA-like)21 and SALSA (SAGA altered, Spt8 absent)22-24. SAGA, SLIK and SALSA contain the lysine acetyltransferase (KAT) Gcn521-23, with lysine 14 on histone H3 (H3K14ac) as a substrate, but differ in their abundance, the genes they regulate and subunit composition19,24 
The inventors have discovered that H3K18 acetylation, is central to a mechanism that controls the balance between cell growth and longevity. They have also identified a number of genes involved in the SAGA SLIK and SALSA complexes whose disruption results in an increase in chronological lifespan.